while president obama did not use the word terrorism when he addressed the nation earlier daring the message was clear. of. >> we still do not know who did this. or why. and people shouldn't jump to conclusions before we have all the facts. but make no mistake. we will get to the bottom of this. we will find out who did this. we'll find out why they did this. any response, any responsible individuals, any responsible groups will feel the full weight of justice. >>reporter: the fbi has taken charge of the investigation into today's bombings in bosto boston. authorities shedding if light on motive or who may have carried out this attack. and police say they have no suspect in custody officials in washington say there has been no immediate claim of responsibility. >> number of people from the bay area witness the explosion. they were there and narrowly escaped injury. 7 news reporter laura anthony with some dramatic accounts of what happed in boston today. >> it was just chaotic. >>reporter: he's a well known marathoner who screws finished his boston mile an hour thon when he heard sire